Craigslist: A good website to get less valuable items, like clothes or other garage sale type items.

Thompson recommends meeting with the seller in person at a safe place to exchange goods.

eBay: According to Thompson, the internet services company is better for more expensive items, like phones or tablets.

Thompson said sellers can almost always make more money selling unwanted items online compared to selling it at a garage sale.

eBay has a feature to ensure you’ll make the amount you want when selling certain items.

“eBay has a price matching options on some of the newer phones where they guarantee the phone will sell at a certain price,” Thompson said. “If it doesn't they'll give you the difference in eBay credits.”

Thompson said the price match features encourages sellers to offer items at a lower price. He also warns online consumers to beware of scammers.

Walmart mobile app: The app will notify mobile users when items go on sale. Another feature is if a consumer bought a product that wasn’t on sale, the consumer can bring it back and get some extra cash.

The Walmart app also has the Savings Catcher feature. If a local competitor has a lower advertised price on a product, the consumer gets an eGift Card for the difference back.

Thompson said many grocery store chains like Kroger and Food City have apps that help monitor deals too.

Retail Me Not is also a popular app for coupons and deals on clothes shopping.